Although all Conus have a poison injecting apparatus, only a few are considered dangerous to human beings. The key is what they eat. Conus species that feed on small worms and other invertebrates have a radular "dart" just large enough and a venom just powerful enough to kill such small feeble prey. Such cones are harmless to people. It is the fish-eating cones that are dangerous. They have a large dart (more like a small harpoon). Also, they either have a more potent venom, or inject a much greater dose of venom, or both (I'm not sure which of these best describes the actual fact). This enables them to rapidly incapacitate a living fish. It also makes them dangerous to humans. The "big three" of course are Conus geographus, Conus striatus, and Conus textile. But there are a number of others that are potentially dangerous, even though they have not caused human deaths. Conus tulipa is one that comes to mind, and a few others - I don't have reference materials here at work. I wouldn't expect Conus perplexus to be dangerous. The fish-eating cones tend to have a wide aperture, which enables them to swallow a fish after harpooning it. One word of caution - it is always possible that a particular person might have an individual sensitivity to Conus venom, just as some people are hypersensitive to bee venom. In such a case, any cone capable of penetrating the skin could theoretically be dangerous. Paul M. Rhode Island, U.S.A.